This application describes a five-year prospective longitudinal study of visual function in glaucoma, which builds upon prior work in this area during two previous grant periods. This study will use a variety of psychophysical tests of visual function to determine the nature and extent of glaucomatous vision loss, and will address the relationship of vision loss to progression of disease, genetic markers, and clinical management. Specific Aims. A. To continue this multivariate approach for analysis of the functional changes in vision associated with glaucoma and to delineate further the relationship of these changes to underlying physiological mechanisms. B. To improve diagnostic and analysis techniques encompassing several measures of visual function. C. To improve techniques for evaluating progression in order to better monitor effectiveness of current and new therapies. D. To delineate the relationship between visual function loss associated with glaucoma and the presence or absence of certain molecular genetic markers. Subjects. The study includes ongoing enrollment. We will have 450 patient eyes tested on standard, SWAP, FDP and MAP fields, who agree to complete the five year study. In addition, we have an extensive database for all subjects with total n of 1295, over 569 of these with SWAP. We have also developed a collaboration with Dr. Jeffrey Liebmann to provide 500 African-American eyes for analysis over the 5 years of this proposal. These patients are clinically well-characterized and our database includes information such as risk factors, medical history, other influencing disease, subtypes of glaucoma, stereophoto grades, all vision testing, measures of optic nerve structure, intraocular pressure history, medications, surgeries, and more. To our knowledge, this extensive database is unique, encompassing more measures of visual function and optic nerve structure over a considerably longer time frame than any other laboratory. Methods. The psychophysical tests are designed to isolate various visual functions. We will use a variety of statistical methods (signal detection theory, Cox proportional hazard modeling, survival analysis, progression algorithms) to determine best parameters for sensitivity and specificity of each, rate and pattern of defect, reproducibility of results and clinical utility. In addition, the relationship to genetics and ethnic group will be determined. Conclusion. The results from the proposed experiments should provide a greater understanding of the underlying damage to vision associated with glaucoma, the comparative progression of loss over time, and the likelihood of predicting which patients are most at risk due to genetic, ethnic or other factors.